I am currently in possession of an iPhone 4 Verizon CDMA running 4.2.8 jailbroken. For undisclosed reasons I am going to restore it to 4.2.10 which is the latest firmware for this iPhone. Later on, I will need to downgrade it to 4.2.8 to jailbreak it. What steps to I need to take before I restore it such as backing up certain "blobs" or what ever they are so that I can downgrade easily at a later date. As much detail as possible since I am not exactly a Steve Jobs or a comex when it comes to these things.